Glossary

CFB Graphs Advanced Stats Glossary

A running list of features, stats, and FAQ about the numbers on this site.

Leaderboards:

• EPA: Expected Points Added EPA translates yards to points in context. A 3 yard gain on 1st and 10 is bad; a 3 yard gain on 3rd and 2 is good. How can we compare? EPA takes into account the down, distance, yardline, and game state of each play to calculate the added point value of every play. EPA is an explosiveness-weighted measure of success: how often did you provide positive value, and on average, how much positive value did you add? It is analagous, roughly, to wOBA in baseball. A higher EPA on offense is good, and a lower EPA on defense is good.

  • EPA/Pass: A pass is a play where the quarterback threw the ball. When you see “EPA/Pass”, you see the EPA per play when a quarterback attempted a pass. That filters out scrambles and sacks, both of which are passes, but you can see EPA breakdowns for scrambles and sacks on the team pages.

  • EPA/Rush: A rush is not a pass, specifically a designed rush. Scrambles and Sacks are not counted.

  • EPA/Play accounts for every offensive snap.

  • EPA60: Total EPA based on a set unit of 60 offensive plays.

• MARGIN: EPA MARGIN A weighted average of offensive and defensive EPA that is a quick measure of overall team efficiency. It is slightly weighted towards offense, as to reflect reality on-field.

• SRte: Success Rate: Success rate uses EPA to create a binary measure of efficiency: how frequently did you improve your situation? A success is any play where EPA=>0, and a failure is any play with EPA <0.

  • Pass SRte: When your team attempted a pass, how often was it successful? This includes all dropbacks, including scrambles and sacks.

  • Rush SRte: When your team rushed the ball, how often was it successful?

• Record: Wins and Losses on the season

• xRecord: Expected Wins and Losses based on the stats from each game. A large difference between expected and actual record insinuates that a team was better than their record.

• Garbage Time: Any drive where a team is up or down by such an egregious amount that backups are playing and the results are not informative as to the relative quality between teams. Additionally, any drive that contains a kneel down, or end of half drives of three or fewer plays.

Team Pages:

• The number you see to the left of the team is the EPA Margin rank.
• Some Stats from the Header and Schedule:
  • Win Pct: Actual Win Percentage
  • xWin Pct: Expected Win Percentage based on stat profile
  • Diff: The difference in actual and expected win percentage for a team
  • PPG Margin: Actual Points Per Game Margin
  • xPTS Margin: xPoints Per Game Margin (Based on Drive Quality)
  • EPA/G Margin: Total EPA per Game Margin (Based on Play Efficiency)
  • First Rte: How often a team earned a first down on first or second down. Alternatively, how often a team avoided third downs on a series.
  • ED EPA: Early Downs (1st and 2nd) EPA. A split here provides a little better insight into which teams move the ball more consistently early on.
  • ED Rush Rte: A measure of style; how often does a team run on first and second down, where tendancies are less dictated by context?
  • Avg 3rd: The average 3rd down distance faced.
  • 3rd Conv: 3rd down conversion rate; how often did a team extend a drive?
  • AYDS: Pct of available yards gained on a drive.
  • Avg FP: Average Starting Field Position of drives
  • Eckel: A “quality possession”, named after the Navy Fullback. A drive qualifies as a quality possession if a team scores a big play touchdown or gets a first down inside the opponent’s 40-yard line.
  • Eckel Rte: How often a team creates a quality possession, a measure of opportunity.
  • Pts/Eckel: Points per quality possession, a measure of finishing ability.
• Player Stats, All Adjusted for Garbage Time
• QBs:
  • COMP %: Completion Pct
  • First Rte: How often a QB pass turns into a first down.
  • Scramble Rte: What percent of dropbacks does a QB scramble?
  • EPA/Scramble: How much value does he add on scrambles?
  • Sack EPA: Total negative value added by sacks.
• Rushers:
  • Third Usage: What percent of a rushers attempts came on third down?
  • First Down: How frequently a rusher earned a first down.
  • AY%: The percent of available yards a rusher earned, on average, divided by the average distance. A measure of partial success.
• Targets:
  • EPA/TGT: EPA/Play on which the player was targeted with a pass.
  • TGT Share: The percent of total team targets a receiver earned.
• Defender:
  • Tackle Share: Pct of total team tackles
  • Stop: A play where the defender makes a tackle that results in a failed play by the offense.
  • Stop Share: Pct of total team stops
  • Drive Kills: Stops on third or fourth down.
  • Drive Kills Share: Pct of total team third down stops

Data:

• Where do you get your data? Data comes from the NCAA.com website.
• Will you share your data? At the current time, I don’t have the bandwidth to manage any kind of data distribution, but leaderboards are available for download.
• How do you make [x]? With a lot of elbow grease and googling, usually in R Studio.